Piano action



April 2, 1940. A. A. DAVIDSON PIANO ACTION Filed Feb. '7. 1938 ATTRNEY.

Patented Apr. 2, 1940 UNITED STATES PATENT OFFICE PIANO ACTION Application February 7, 1938, Serial No. 189,091

3 Claims.

, My invention relates particularly to piano aclions designed for grand pianos, and it has as its main objective to provide a piano action mechanism which is much more simple and of fewer parts than the actions now in use and at the same time be just as eifective, accurate and sensitive as the best of actions now in use.

Other objects of my invention are: to provide roller elements between the jack and the hammer butt, whereby to secure a smoother and more sensitive action and let-off to provide in a mechanism of the character referred to means for adjusting the jack position and its spring actuating and abutment means for greater accuracy; to provide a mechanism of the character referred to in which the usual repetition lever mechanism is done away with and a simplification accomplished; to provide in such a mechanism a construction and arrangement whereby the whip rail is above the whip, thereby permitting a lower position of the key assembly; and, in general to provide an improved and simplified piano action of the character referred to.

In order to describe my invention more in detail, I have illustrated the same on the accompanying sheet of drawings which I will now describe:

Figure 1 is a side elevation of a piano key and key action mechanism, with parts shown in section;

Figure 2 is an enlarged view of certain details; and

Figure 3 is a view of a slight modificationin a detail.

Referring now in detail to the drawing, the supporting key frame is designated 5, the key is designated 6, with the usual key pin 1, and the balance key pin 8. The rear end of said key is provided with two felts, as 9 and ID, on its under side, and with a felt I I, on its top side, and with the usual back check l2. Also mounted in said key 6, rearwardly of the pin 8, is a capstan screw l3, in engagement with a felt M, on the under side of the whip I5, pivotally connected with the whip rail I6, which is above the whip, as clearly shown in the drawing. Pivotally connected at its lower end to the whip is a jack ll, having in its upper end a roller l8. Said jack I! has a felt I9 mounted on one side, and a holding pin with felt 2|, on its other side, over which telescopes a jack spring 22, as indicated in Fig. 2, the upper end of said jack spring telescoping over another pin or threaded screw, as 23, threaded through a butt rail 24, and adjustable to regulate the tension of said jack spring 22. A felt is shown at the end of the spring on said pin 23, with adjust ment nut 26 threaded on said pin, as shown. Mounted on the whip is a member 21, through which is an adjustable abutment screw 28, against the head of which the felt IS, on said jack rests. Mounted on the jack H, is a jack moving toe 29, positioned to abut a felt 30, on the lower end of an adjustable screw 3|, through a rail 32, whereby, after said jack has moved upwardly bodily with the whip l5, said toe 29 engages with said felt 30, to cause a relative movement of the upper end of said jack, for a purpose referred to again.

Connected with the butt rail 24, by means of a base member 33, is a butt 34, with a hammer at the free end of said butt, said hammer having a downwardly projecting portion 35 to be engaged by the back check l2, after the hammer has struck the wire, designated W. A felt pad 36 is mounted on top of the Whip rail [6, to receive said butt 34 in its rest position.

The usual damper 31, with wire 38, connected with a damper lever 39 is provided, operated by the rearward end of the key 6, as will be understood from the drawing. 25

Mounted on the underside of the butt 34, is an oval shaped, felt covered, engagement member 40, positioned to be engaged by the roller 18 on the upper end of the jack, as shown.

In Fig. 3, I have shown a portion of the structure shown in Fig. 1, including the rail 24, member 33 and a different hammer butt, designated 34, having mounted in said hammer butt a roller element 4|. On the jack, designated I1, I have shown its upper end as fixed and provided with a felt-covered end, 42, positioned to engage the roller element 4|, as indicated. The other parts may be the same as shown in Fig. 1, with the same reference numerals.

Thus in either embodiment or form of the invention, I have provided the roller, felt-covered, contact element, on the jack or the hammer butt, whereby to render more sensitive and frictionless the movement of one of these members on the other, making possible the relative movement of one element on the other as the hammer rebounds,

In the operation of this mechanism, it will be noted that the depression of the 6, lifts its opposite end, and with it, by means of the capstan screw I3, the whip lever I5 is raised at its right hand end, upon which the jack I1 is pivoted. The jack ll moves upwardly endwise, with the roller l8 against the member 40, thus raising the butt or hammer lever 34 until the hammer 3'5 strikes the wire W. Just as the hammer strikes said wire, it rebounds until its lower extension 35 rests against the back check l2, which was raised with the key, but the jack roller it", has rolled outwardly off of the member 0 to let said hammer rebound. This relative movement of the jack l7 and its roller 18 is caused by the toe 28 connected therewith engaging the felt member 33. This movement is thus very sensitive, yet very accurate and positive. The rest position of the jack can be varied by the adjustment of the abutment screw 28, and the tension of the spring 22, bearing on said jack I can be made by turning its screw rod 23. The jack spring 22, in combination with the jack ii, and the roller engagement means at l8-40, or at -l2- ll in Fig. 3, makes it possible to do away with the usual repetition lever and its various parts, thus greatly simplifying the action mechanism and still providing a most sensitive and emcient action.

Another important feature my invention is the new form of key 6, which makes possible a considerable reduction in the vertical height of the action mechanism. This enables me to provide in a grand piano a much narrower assemblage of the action.

The key S, at its rearward end is much lower in its functioning parts than the usual straight keys now in use. The under side of said key 6 is provided with double drop portions, as at 6 and 6", giving a lower rest point at the balance pin 8. This also allows sufficient thickness of the balance rail 5 to properly anchor the balance pin .3 therein. This lower rest position gives a greater throw of the back check or hammer stop l2, and also makes for clearance of the hammer at the down position. The top part of the key, because of this novel construction and arrangement, can be cut out, as indicated at 6a, to provide a much lower position for the whip lever l5 and the capstan screw 13, as will be understood from Fig. 1. In order to prevent the rearward end of the key from striking the rear key rail, the two felts 9 and I0 are provided, as indicated.

Thus I have provided a novel key, having a dip in the key form between the balance pin 8 and the rear key rail, and so far as known, this is new.

I am aware that many changes in the details of construction and arrangement can be made in my invention as here illustrated for explanatory purposes, without departing from the spirit thereof, and I do not, therefore, limit the invention to the showing made, except as I may be limited by the hereto appended claims.

I claim:

1. In a piano action, the combination with a piano key, whip lever, butt lever and hammer, of a jack pivotally connected at its lower end to the end of said whip lever and extended up to said butt lever, anti-friction roller means interposed between the upper end of said jack and the underside of said butt lever to permit free relative movement between the end of said jack and said butt lever as said jack is moved by the whip lever to move the butt lever and hammer operatively, means connected with said jack to cause a relative movement of the upper end of said jack lever to permit rebound of said butt lever and hammer, and a spring acting on said jack to return it to operating position for repeat action Without completely releasing the key.

2. In a piano action, the combination of a piano key having its rear end lowered below the plane of the top of the key proper, a whip lever pivotally seated in said lowered part and longitudinally therein, a butt lever and hammer, a jack pivotally connected at its lower end to the end of said Whip lever and extended up to the butt lever, anti-friction means interposed between the upper end of said jack and the undo side of said butt lever to permit free relative movement between the end of said jack and said butt lever as said jack is moved by the whip lever to move the butt lever and hammer operatively, means connected therewith for causing a quick relative movement of said jack after its operative movement to permit a rebound of said butt lever and hammer, and a spring acting directly on said jack to return it to operating position for repeat action without completely reeasing the key.

3. In a piano action, a key body having its rear end portion lowered as to its top surface below the plane of the top surface of the key body proper, to provide a recess for a whip lever, a whip lever pivotally mounted in said recess, longitudinally thereof, a jack pivotally connected at its lower end to the end of said whip lever and extended upwardly for operating a butt lever and hammer, a butt lever and hammer, an engaging element on the under side of said butt lever, a roller on the upper end of said jack operating on said engaging element, means connected therewith for moving said jack laterally away from said engaging element to permit rebound of said butt lever and hammer, and a spring acting on the jack to move it back into aligned engagement with said engaging element without fully releasing the key for repeat action.

ASHLEY A. DAVIDSON. 

